On Fri, Mar 08, 2019 at 03:16:03PM -0600, Josh Poimboeuf wrote: > On Thu, Mar 07, 2019 at 12:45:31PM +0100, Peter Zijlstra wrote: > > Having DF escape is BAD(tm). > > > > Suggested-by: Linus Torvalds <[email protected]> > > Signed-off-by: Peter Zijlstra (Intel) <[email protected]> > > Can you elaborate on why (in the patch description)? Did this actually > find any occurrences?
Nope, didn't find anything. Also, all DF users are in asm so I didn't really expect any. Having it escape would probably result in fairly instant wreckage though. DF=1 results in things like rep mov going _backwards_.
